Diffuse paediatric cerebellar glioma: two identical imaging phenotypes of an extremely rare entity with disparate pathology.

Although the posterior fossa is a common location for paediatric brain tumours [1], diffuse glioma isolated to the cerebellum is an extremely rare imaging entity. Only two cases of isolated diffuse paediatric cerebellar glioma have been reported in the English language to the best of our knowledge [2, 3], and only one of these cases had a similar imaging phenotype to our cases [3]. Although somewhat similar to Lhermitte-Duclos (dysplastic gangliocytoma of the cerebellum), the appearances are distinct from other neoplastic entities of the paediatric posterior fossa. Clinical presentation and neurological examination findings are vital however to help differentiate other diffuse pathologies involving the cerebellum such as rhombencephalitis. Presented here are two diffuse cerebellar gliomas in children under the age of 3 with near identical imaging phenotypes demonstrating differing histological and molecular genetic profiles.

Using an Online Tool to Apply a Person-Centred Approach in Audiological Rehabilitation: A Pilot Study.

This study aimed to explore the experiences of adult clients with hearing loss and their audiologists in using an online tool, the Living Well Tool (LWT), during initial audiology appointments. The LWT is designed to help clients identify when and where it is most important for them to communicate effectively and live well with hearing loss. A total of 24 adult clients with hearing loss and two audiologists participated in this study. Clients were invited to complete the LWT prior to their next audiology appointment, however, most clients chose to use the LWT in-session with their audiologist. Following the appointment, clients and audiologists participated in individual qualitative semi-structured interviews to explore their experiences of using the LWT, and the extent to which the LWT facilitated person-centred care. Qualitative analysis five key themes which reflected participants' experiences and perceptions of using the LWT: (1) the LWT enhances audiological care; (2) the LWT supports person-centred audiological care; (3) the use of the LWT should be individualised; (4) users value comprehensiveness; and (5) users value accessibility. This study demonstrated that the LWT supported the provision of person-centred audiological care, providing a flexible, comprehensive and accessible means for audiologists to gain an understanding of their clients' needs and preferences. However, it was also noted that the use of a tool must be individualised and accessible for all.

Implementation science challenges: hearing care professionals identify barriers to clinical research.

OBJECTIVES: Conducting research in clinical settings is challenging. The aim of this study was to increase our understanding of hearing care professionals' perceptions of barriers to participating in such research. DESIGN: A modified group concept mapping approach was used to gain anonymous responses from 124 hearing care professionals to the statement: "One reason why it is hard to conduct intervention research studies in my centre/practice is….". Participants were asked for reasons other than 'time' as this is universally reported as a barrier to clinical research. RESULTS: A total of 107 distinct reasons were provided by participants and these were sorted into 5 clusters: "Competing demands/pressures" (18 statements), "Not a priority for management/organisation" (14 statements), "Lack of opportunity/support" (19 statements), "Clinician's knowledge, confidence, and beliefs" (24 statements), and "Recruitment/adherence to protocols is challenging" (32 statements). Identified barriers were generally similar to those reported in other healthcare settings, with unique barriers being those associated with a fear of scrutiny and lack of trust in the "academic elite". CONCLUSION: Findings highlight the importance of researchers, clinicians, and clinic managers working together at all stages of the research process in order for clinical research to be successful.

Linear interactions between intraocular, intracranial pressure, and retinal vascular pulse amplitude in the fourier domain.

PURPOSE: To compare the retinal vascular pulsatile characteristics in subjects with normal (ICPn) and high (ICPh) intracranial pressure and quantify the interactions between intraocular pressure, intracranial pressure, and retinal vascular pulse amplitude in the Fourier domain. MATERIALS AND METHODS: Twenty-one subjects were examined using modified photoplethysmography with simultaneous ophthalmodynamometry. A harmonic regression model was fitted to each pixel in the time-series, and used to quantify the retinal vascular pulse wave parameters including the harmonic regression wave amplitude (HRWa). The pulse wave attenuation was measured under different ranges of induced intraocular pressure (IOPi), as a function of distance along the vessel (VDist). Intracranial pressure (ICP) was measured using lumbar puncture. A linear mixed-effects model was used to estimate the correlations between the Yeo-Johnson transformed harmonic regression wave amplitude (HRWa-YJt) with the predictors (IOPi, VDist and ICP). A comparison of the model coefficients was done by calculating the weighted Beta (ßx) coefficients. RESULTS: The median HRWa in the ICPn group was higher in the retinal veins (4.563, interquartile range (IQR) = 3.656) compared to the retinal arteries (3.475, IQR = 2.458), p<0.0001. In contrast, the ICPh group demonstrated a reduction in the median venous HRWa (3.655, IQR = 3.223) and an elevation in the median arterial HRWa (3.616, IQR = 2.715), p<0.0001. Interactions of the pulsation amplitude with ICP showed a significant disordinal interaction and the loss of a main effect of the Fourier sine coefficient (bn1) in the ICPh group, suggesting that this coefficient reflects the retinal vascular response to ICP wave. The linear mixed-effects model (LME) showed the decay in the venous (HRWa-YJt) was almost twice that in the retinal arteries (-0.067±0.002 compared to -0.028±0.0021 respectively, p<0.00001). The overall interaction models had a total explanatory power of (conditional R2) 38.7%, and 42% of which the fixed effects explained 8.8%, and 5.8% of the variance (marginal R2) for the venous and arterial models respectively. A comparison of the damping effect of VDist and ICP showed that ICP had less influence on pulse decay than distance in the retinal arteries (ßICP = -0.21, se = ±0.017 compared to [Formula: see text], se = ±0.019), whereas the mean value was equal for the retinal veins (venous [Formula: see text], se = ±0.015, ßICP = -0.42, se = ±0.019). CONCLUSION: The retinal vascular pulsation characteristics in the ICPh group showed high retinal arterial and low venous pulsation amplitudes. Interactions between retinal vascular pulsation amplitude and ICP suggest that the Fourier sine coefficient bn1 reflects the retinal vascular response to the ICP wave. Although a matrix of regression lines showed high linear characteristics, the low model explanatory power precludes its use as a predictor of ICP. These results may guide future predictive modelling in non-invasive estimation of ICP using modified photoplethysmography.

Disentangling 'sciatica' to understand and characterise somatosensory profiles and potential pain mechanisms.

OBJECTIVES: The study aimed to investigate if patients with lumbar radicular pain only and those with combined lumbar radicular pain + radiculopathy differ in their somatosensory profiles and pain experiences. METHODS: Quantitative sensory testing (QST) was performed in 26 patients (mean age 47 ± 10 years, 10 females) with unilateral leg pain in the L5 or S1 distribution in their main pain area (MPA) and contralateral mirror side, in the relevant foot dermatome on the symptomatic side and in the hand dorsum. Pain experience was captured on the painDETECT. RESULTS: Eight patients presented with lumbar radicular pain only and 18 patients with combined radicular pain + radiculopathy. Patients with radicular pain only demonstrated widespread loss of function (mechanical detection) bilaterally in the MPA (p<0.003) and hand (p=0.002), increased heat sensitivity in both legs (p<0.019) and cold/heat sensitivity in the hand (p<0.024). QST measurements in the dermatome did not differ compared to HCs and patients with radiculopathy. Patients with lumbar radiculopathy were characterised by a localised loss of function in the symptomatic leg in the MPA (warm, mechanical, vibration detection, mechanical pain threshold, mechanical pain sensitivity p<0.031) and dermatome (mechanical, vibration detection p<0.001), consistent with a nerve root lesion. Pain descriptors did not differ between the two groups with the exception of numbness (p<0.001). Patients with radicular pain did not report symptoms of numbness, while 78% of patients with radiculopathy did. CONCLUSIONS: Distinct differences in somatosensory profiles and pain experiences were demonstrated for each patient group, suggesting differing underlying pain mechanisms.

Deep Brain Stimulation and Swimming Performance: A Randomized Within-Person Crossover Study.

OBJECTIVE: To determine whether deep brain stimulation (DBS) causes swimming impairment, we systematically compared swimming ability between DBS on vs off in 18 patients. METHODS: We conducted a randomized blinded crossover study, comparing swimming ability between DBS on vs off, within participants. Participants swam 3 laps of front crawl and 3 laps of breaststroke. Prespecifed primary outcomes were proportion of lap completed, lap time, and Aquatic Skills Proficiency Assessment (ASPA) score. Prespecified secondary outcomes were a qualitative description of marked changes observed. RESULTS: Eighteen participants with Parkinson disease (n = 13), essential tremor (n = 3), Tourette syndrome (n = 1), or posttraumatic brain injury proximal tremor (n = 1), treated with posterior subthalamic area (n = 15) or globus pallidus interna (n = 3) DBS were assessed. There was no significant effect of DBS on/off status on any outcome measure for front crawl or breaststroke. Three participants showed changes in both qualitative and quantitative assessments. Of these, 1 participant displayed reduction in swimming ability: impairment in all outcomes with DBS on, normalizing with DBS off (the same individual as previously reported). The participant displayed difficulty coordinating limb movement as well as postural control. Two participants showed improvements in lap time and ASPA scores with DBS on. CONCLUSION: Overall DBS did not impair swimming performance, although 1 patient demonstrated a stimulation-induced drowning hazard. There were no anatomic or clinical features unique to the individual with swimming impairment. Patients should be warned about the possibility of DBS-induced drowning hazard and should swim with capable supervision after DBS. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with implanted DBS electrodes, the stimulation on condition, compared with stimulation off, did not significantly impair swimming performance. A formal assessment of unblinding would have been helpful.

Delayed oculomotor nerve palsy associated with a ruptured anterior communicating aneurysm: Case report.

BACKGROUND AND IMPORTANCE: Oculomotor nerve palsy (ONP) is usually associated with posterior communicating (PCOM) aneurysms. ONP in patients with anterior circulation aneurysms are extremely rare, with only a handful of such published cases to date. There is currently no accepted mechanism to explain this clinical finding. CLINICAL PRESENTATION: We describe a case of a 60-year-old female that benefitted from endovascular coiling of a ruptured anterior communicating (ACOM) aneurysm. In the following days, she clinically deteriorated and benefitted from another digital subtraction angiography (DSA) with intravascular verapamil for suspected vasospasm, and subsequently developed a right ONP. CONCLUSION: Although classically related to PCOM aneurysm, ONP may be associated with ACOM aneurysms. The causative mechanism is unclear, but vasospasm may alter the microvascularisation of the oculomotor nerve, leading to ischemia.

The Magnetic Resonance Imaging (MRI)-Directed Implantable Guide Tube Technique: Accuracy and Applications in Deep Brain Stimulation.

OBJECTIVE: The magnetic resonance imaging (MRI)-directed implantable guide tube technique allows for direct targeting of deep brain structures without microelectrode recording or intraoperative clinical assessment. This study describes a 10-year institutional experience of this technique including nuances that enable performance of surgery using readily available equipment. METHODS: Eighty-seven patients underwent deep brain stimulation surgery using the guide tube technique for Parkinson disease (n = 59), essential tremor (n = 16), and dystonia (n = 12). Preoperative and intraoperative MRI was analyzed to measure lead accuracy, volume of pneumocephalus, and the ability to safely plan a trajectory for multiple electrode contacts. RESULTS: Mean target error was measured to be 0.7 mm (95% confidence interval [CI] 0.6-0.8 mm) in the anteroposterior plane, 0.6 mm (95% CI 0.5-0.7 mm) in the mediolateral plane, and 0.8 mm (95% CI 0.7-0.9 mm) in the superoinferior plane. Net deviation (Euclidean error) from the planned target was 1.3 mm (95% CI 1.2-1.4 mm). Mean intracranial air volume per lead was 0.2 mL (95% CI 0.1-0.4 mL). In total, 52 patients had no intracranial air on postoperative imaging. In all patients, a safe trajectory could be planned to target for multiple electrode contacts without violating critical neural structures, the lateral ventricle, sulci, or cerebral blood vessels. CONCLUSIONS: The MRI-directed implantable guide tube technique is a highly accurate, low-cost, reliable method for introducing deep brain electrodes. This technique reduces brain shift secondary to pneumocephalus and allows for whole trajectory planning of multiple electrode contacts.

A qualitative systematic review of experiences of persons with dementia regarding transition to long-term care.

INTRODUCTION: The current qualitative systematic review identified and examined critically the literature on how persons with dementia experience transitions to long-term care. Results are intended to help develop guidelines for future care and research. METHOD: A search was conducted of OvidSP, SCOPUS, Web of Science, ProQuest, PsycINFO, CINAHL, AgeLine and Informit databases. In total, 4705 articles were reviewed (published 1954-2018). A textual narrative approach was used to synthesise the findings of the included articles. RESULTS: Seven articles met inclusion criteria (five using data collected from interviews with persons with dementia and two using reports from a proxy). Overall, the findings showed that transition to long-term care possesses varied meanings for persons with dementia, is often not the decision of the persons with dementia, and is a process throughout which social connections remain important. DISCUSSION: Accounts of the experiences of persons with dementia regarding transitions from community to long-term care show that they and their families should be supported: with respect to their individual contexts, to share the positives and negatives of the transition experiences, to make decisions together, and to maintain old and establish new social connections.

Attaining and assessing the Australian interprofessional learning competencies.

Interprofessional collaboration is critical for optimal healthcare. Preparing for a collaborative, practice-ready workforce, the Interprofessional Learning Competencies (IPLCs) were adopted for accreditation of Australian entry-level health, nursing and medical tertiary training programs. In order to meet new accreditation standards, activities which facilitate and assess IPLC attainment must be identified. Interprofessional education programs have not evaluated student interprofessional learning activities using the Australian IPLCs. This project evaluates students' experiences of the IPLCs during 'Inspiring Health,' a community-based interprofessional placement, and determines whether reflections can effectively assess IPLC attainment. Forty-nine students from seven Flinders University health and social science programs completed written reflections about four self-selected IPLCs. The results indicated that students had opportunities to attain all the IPLCs. Their reflections were analyzed using thematic analysis. Three themes were identified: the processes by which students learned, the outcomes of their learning, and the factors that influenced their learning. Ultimately, these findings describe a beneficial community-based interprofessional learning activity for attainment of the Australian IPLCs and provide evidence that student reflections can be used to assess the Australian IPLCs.

Surgical management of symptomatic cavum septum pellucidum cysts: systematic review of the literature.

Cavum septum pellucidum (CSP) and cavum vergae (CV) cysts are commonly found incidentally. They are usually asymptomatic but may present with symptoms related to obstructive hydrocephalus. There is no consensus about the management of symptomatic CSP and CV cysts. We present, to the best of our knowledge, the first systematic review of the different treatment options for symptomatic CSP and CV cysts. We conducted a literature review using PubMed database, searching for cases of symptomatic CSP and CV cysts managed surgically, and published until April 2019. Preoperative characteristics, surgical procedure, and postoperative outcome were analyzed using SPSS® software (Statistical Package for Social Sciences, IBM®). We found 54 cases of symptomatic CSP and CV cysts managed surgically (34 males, 20 females, 1.7/1 male to female ratio). Mean age was 24.3 ± 20.1 years. The most common presentation was headaches (34 patients, 62%), followed by psychiatric symptoms (27 patients, 49.1%). Preoperative radiological hydrocephalus was present in 30 patients (54.5%). The most common surgical procedure was endoscopic fenestration (39 patients, 70.9%), followed by shunting (10 patients, 18.2%), open surgery (3 patients, 5.5%), and stereotactic fenestration (1 patient, 1.8%). Complete resolution of symptoms was achieved in 36 patients (65.5%) and partial resolution in 7 patients (12.7%), and symptoms were unchanged in 2 patients. The present review suggests that surgical treatment could provide resolution of the symptoms in most of the cases, regardless of the procedure performed. Although mean follow-up was short among the studies, recurrence rate was low.

Defining the Border of the Subthalamic Nucleus for Deep Brain Stimulation: A Proposed Model Using the Symmetrical Sigmoid Curve Function.

BACKGROUND: The subthalamic nucleus (STN) is an important target during deep brain stimulation (DBS). Accurate lead placement is integral to achieving satisfactory clinical outcomes; however, the STN remains a structure whose visualization is highly variable with borders often difficult to define. We aimed to develop an objective method of evaluating the visibility of the STN on preoperative magnetic resonance imaging (MRI) to standardize future comparative assessments between imaging protocols and patient-specific parameters. METHODS: An imaging study of 64 prospectively collected patients undergoing bilateral DBS of the STN for various movement disorders was performed with institutional approval. MRI scans were acquired using a uniform protocol involving general anesthesia, cranial fixation in a Leksell stereotactic frame, and long acquisition times using a 3T MRI scanner. The images were analyzed using the iPlan Stereotaxy, version 2.6, workstation. High-resolution T2-weighted axial sections were evaluated, and the voxel values in the region of the presumed posterior border of the STN (as defined by the operating neurosurgeon) were obtained. A 4-parameter logistic symmetrical sigmoid curve was used to map the voxel values as they progressed from within to outside the region of the STN border. The inflection point and Hill coefficient of this symmetrical curve was calculated to provide objective information on the location and clarity of the STN border, respectively. These findings were compared with the surgeon's judgment of the STN border. To demonstrate the use of the sigmoid curve, the patients' head volumes were also calculated and evaluated to assess whether larger head volumes adversely affected STN visibility. RESULTS: The symmetrical sigmoid curve model provided objective information on the visibility of the STN on T2-weighted MRI scans and could be generated in 86% of the patients. The other 14% of patients had MRI scans that generated linear graphs, indicating the poorest scoring for STN image quality. No correlation between head volume and STN visibility was identified. CONCLUSIONS: Our proposed statistical model allows for standardized examination of the visibility of the STN border for DBS and has potential for both clinical and academic applications.

Gesture, communication, and adult acquired hearing loss.

Nonverbal communication, specifically hand and arm movements (commonly known as gesture), has long been recognized and explored as a significant element in human interaction as well as potential compensatory behavior for individuals with communication difficulties. The use of gesture as a compensatory communication method in expressive and receptive human communication disorders has been the subject of much investigation. Yet within the context of adult acquired hearing loss, gesture has received limited research attention and much remains unknown about patterns of nonverbal behaviors in conversations in which hearing loss is a factor. This paper presents key elements of the background of gesture studies and the theories of gesture function and production followed by a review of research focused on adults with hearing loss and the role of gesture and gaze in rehabilitation. The current examination of the visual resource of co-speech gesture in the context of everyday interactions involving adults with acquired hearing loss suggests the need for the development of an evidence base to effect enhancements and changes in the way in which rehabilitation services are conducted.

Association of quantitative sensory testing parameters with clinical outcome in patients with lumbar radiculopathy undergoing microdiscectomy.

BACKGROUND/AIM: This study aimed to establish the somatosensory profile of patients with lumbar radiculopathy at pre-and post-microdiscectomy and to explore any association between pre-surgical quantitative sensory test (QST) parameters and post-surgical clinical outcomes. METHODS: A standardized QST protocol was performed in 53 patients (mean age 38 ± 11 years, 26 females) with unilateral L5/S1 radiculopathy in the main pain area (MPA), affected dermatome and contralateral mirror sites and in age- and gender-,and body site-matched healthy controls. Repeat measures at 3 months included QST, the Oswestry Disability Index (ODI) and numerous other clinical measures; at 12 months, only clinical measures were repeated. A change <30% on the ODI was defined as 'no clinically meaningful improvement'. RESULTS: Patients showed a significant loss of function in their symptomatic leg both in the dermatome (thermal, mechanical, vibration detection p < .002), and MPA (thermal, mechanical, vibration detection, mechanical pain threshold, mechanical pain sensitivity p < .041) and increased cold sensitivity in the MPA (p < .001). Pre-surgical altered QST parameters improved significantly post-surgery in the dermatome (p < .018) in the symptomatic leg and in the MPA (p < .010), except for thermal detection thresholds and cold sensitivity. Clinical outcomes improved at 3 and 12 months (p < .001). Seven patients demonstrated <30% change on the ODI at 12 months. Baseline loss of function in mechanical detection in the MPA was associated with <30% change on the ODI at 12 months (OR 2.63, 95% CI 1.09-6.37, p = .032). CONCLUSION: Microdiscectomy resulted in improvements in affected somatosensory parameters and clinical outcomes. Pre-surgical mechanical detection thresholds may be predictive of clinical outcome. SIGNIFICANCE: This study documented quantitative sensory testing (QST) profiles in patients with lumbar radiculopathy in their main pain area (MPA) and dermatome pre- and post-microdiscectomy and explored associations between QST parameters and clinical outcome. Lumbar radiculopathy was associated with loss of function in modalities mediated by large and small sensory fibres. Microdiscectomy resulted in significant improvements in loss of function and clinical outcomes in 85% of our cohort. Pre-surgical mechanical detection thresholds in the MPA may be predictive of clinical outcome.

Endoscopic Fenestration of Cavum Septum Pellucidum Cysts to the Third Ventricle: Technical Note.

BACKGROUND AND IMPORTANCE: Cavum septum pellucidum (CSP) and cavum vergae (CV) cysts are common incidental findings on imaging studies. However, they may rarely present with symptoms related to the obstruction of the foramen of Monro by the cyst leaflets. There is no consensus regarding the management of symptomatic CSP and CV cysts. We present an original transcavum interforniceal endoscopic fenestration technique. The step-by-step surgical procedure and two illustrative cases are presented. CLINICAL PRESENTATION: A 31-yr-old male and a 24-yr-old woman presented with symptomatic CSP and CV cysts. For both patients, neuronavigation was used to plan the procedure. An endoscope was introduced into the cyst through a right frontal burr-hole. After an examination of the endoscopic anatomy, a communication between the cyst and the third ventricle was performed using an endoscopic forceps. In both cases, directly after the fenestration, cerebrospinal fluid (CSF) passed through the communication, and the collapse of the cyst was appreciated. Symptoms were relieved in both patients, and neuropsychological assessment improved. Postoperative imaging showed a reduction in the cyst bulge, and patent foramen of Monro. CONCLUSION: Endoscopic fenestration of CSP and CV cysts to the third ventricle through an interforniceal navigated approach is a feasible and efficient surgical procedure. Theoretical advantages include a single tract through noneloquent brain, a perpendicular trajectory to the membrane for fenestration, and a large CSF space beyond the fenestration point.

Parental experiences of the diagnosis of permanent childhood hearing loss: a phenomenological study.

Objective: The objective of the study was to discover the nature of parental lived experiences of the diagnostic process of Permanent Childhood Hearing Loss (PCHL) and to construct an emotional life-world of parent experience around PCHL.Design: Through an Interpretive Phenomenological Analytical (IPA) framework and subsequent purposive sampling, parents were invited to semi-structured interviews.Sample: Ten parents of children who were identified with PCHL as one or the only permanent childhood disability diagnosed during early childhood were interviewed.Results: Five themes emerged; (a) a received disability, (b) casualties, (c) acceptance in real-time, (d) the unique signature of family life, and (e) audiologists are essential and appreciated guides. The emotional landscape chronicled two concurrent, non-linear affective groupings: the spiral of disorientation, and protective states of righting.Conclusion: Parents require a level of emotional support that exceeds frameworks of counselling. We propose the Dual Process Model as an intermediary model of emotional literacy to address both grieving and coping during the passage from diagnosis to early management. We believe it provides an effortless articulation with the principles of Family-Centred Care philosophies (top down) and behaviours (bottom up) by providing a taxonomy of grieving, coping and parents' movement between the two orientations.

Sudden Onset of Paraparesis Caused by a Hemorrhagic Thoracic Synovial Cyst.

BACKGROUND: Hemorrhage is a rare presentation of spinal synovial cysts, which are usually located in the lumbar spine. They may cause an epidural hematoma and compression of the cauda equina. Infrequently, they may be located in the thoracic spine. CASE DESCRIPTION: We present a case of sudden onset paraparesis caused by hemorrhage in a synovial cyst at a midthoracic level. Clinical, radiologic, and histologic findings are described. CONCLUSIONS: This report describes a unique case of hemorrhagic synovial cyst at the mid-thoracic spine. These lesions are rarely located in the cervico-thoracic spine but should be included in the differential diagnosis of myelopathy.

Modulation of saccades in humans by electrical stimulation of the posterior subthalamic area.

OBJECTIVE: Posterior subthalamic area (PSA) deep brain stimulation (DBS) targeting the zona incerta (ZI) is an emerging treatment for tremor syndromes, including Parkinson's disease (PD) and essential tremor (ET). Evidence from animal studies has indicated that the ZI may play a role in saccadic eye movements via pathways between the ZI and superior colliculus (incerto-collicular pathways). PSA DBS permitted testing this hypothesis in humans. METHODS: Sixteen patients (12 with PD and 4 with ET) underwent DBS using the MRI-directed implantable guide tube technique. Active electrode positions were confirmed at the caudal ZI. Eye movements were tested using direct current electrooculography (EOG) in the medicated state pre- and postoperatively on a horizontal predictive task subtending 30°. Postoperative assessments consisted of stimulation-off, constituting a microlesion (ML) condition, and high-frequency stimulation (HFS; frequency = 130 Hz) up to 3 V. RESULTS: With PSA HFS, the first saccade amplitude was significantly reduced by 10.4% (95% CI 8.68%-12.2%) and 12.6% (95% CI 10.0%-15.9%) in the PD and ET groups, respectively. With HFS, peak velocity was reduced by 14.7% (95% CI 11.7%-17.6%) in the PD group and 27.7% (95% CI 23.7%-31.7%) in the ET group. HFS led to PD patients performing 21% (95% CI 16%-26%) and ET patients 31% (95% CI 19%-38%) more saccadic steps to reach the target. CONCLUSIONS: PSA DBS in patients with PD and ET leads to hypometric, slowed saccades with an increase in the number of steps taken to reach the target. These effects contrast with the saccadometric findings observed with subthalamic nucleus DBS. Given the location of the active contacts, incerto-collicular pathways are likely responsible. Whether the acute finding of saccadic impairment persists with chronic PSA stimulation is unknown.

Expanding current understandings of epistemic injustice and dementia: Learning from stigma theory.

The current paper addresses the nature of epistemic injustice as it may be experienced by persons with dementia. We describe how theoretical models of stigma align with the current model of epistemic injustice through a consideration of the concepts of 'stereotype', 'prejudice' and 'discrimination', shared by the two models. We draw on current understandings of dementia-related stigma to expand understandings of the epistemic injustice faced by persons with dementia. We discuss how these insights may inform the development of mechanisms to uphold the basic human right to speak, to be heard, and to be believed for persons with dementia.